Determining Symmetry of Matrix F: ABA

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Homework Statement



Let A and B be symmetric n x n matrices. Determine whether the given matrix must be symmetric or could be nonsymmetric.

F=ABA

Homework Equations



(AB)^T=B^T A^t


The Attempt at a Solution



So if it's symmetric, that means (ABA)^T=ABA. I decided to make A one term and BA another term and distributed it to be (BA)^T (A)^T=A^T B^T A^T=ABA, making it symmetric.
But I'm not sure if I can evaluate it like this.
 
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That looks perfectly ok to me.
 
Dick said:
That looks perfectly ok to me.

Thanks very much!
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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